Eutectic crystallization in the FeO1.5–UO2+x–ZrO2 system

Results of the investigation of the FeO1.5–UO2+x–ZrO2 system in air are presented. The eutectic position and the content of the phases crystallized at this point have been determined. The temperature and the composition of the ternary eutectic are 1323 ± 7 °С and 67.4 ± 1.0 FeO1.5, 30.5 ± 1.0 UO2+x, 2.1 ± 0.2 ZrO2 mol.%, respectively. The solubilities of FeO1.5 and ZrO2 in the UO2+x(FeO1.5, ZrO2) solid solution correspond to respectively 3.2 and 1.1 mol.%. The solubilities of UO2 and ZrO2 in FeO1.5 are not significant. The existence of a solid solution on the basis of U(Zr)FeO4 compound is found. The ZrO2 solubility in this solid solution is 7.0 mol.%.